Non-rotatable retaining devices



Aug. 14, 1956 A. w. KAMMERER NON-ROTATABLE RETAINING DEVICES Filed Aug.so, 1952 INVENTOR. ec//Ee WKAMMEQEQ,

#will z Y. 2/ 2 ..3 l 4 5 z 2 2 J J nited States Patent O N N-R'OTATABLE RETAINING DEVICES Archer W. Kammerer, Fullerton, Calif.Application August 30, '1952, Serial No. 307,276

3 Claims. (Cl. 308-4) The present invention relates to retaining or lockdevices, and more particularly to devices for securing operative partsof a mechanism in appropriate assembled relation.

An object of the present invention is to provide a retaining devicecapable of being readily and non-rotatably secured to a member on whichit is mounted.

Another object of the invention is to provide a retaining device thatcan be easily mounted on a supporting member and dismantled therefrom,and which has a high load transmitting capacity.

In the drilling of wells, it is sometimes desirable to use a stabilizingor centering device near the drill bit to stabilize or center theequipment in the hole. Diiiiculties are sometimes encountered inretaining the device in place, and in drilling or washing over it in theevent the equipment becomes stuck in the well bore.

Accordingly, a further object-of the invention is to provide a devicefor retaining stabilizing and centering equipment in appropriateposition on a tubular string disposed in a well bore, and in which thedevice can be milled or drilled away readily when the equipment becomesstuck in the well bore;

This invention possesses many other advantages, and has other objectswhich may be made more clearly apparent from a consideration of a formin which it may be embodied. This form is shown in the drawingsaccompanying and forming part of the present specification. It will nowbe described in detail, for the purpose of illustrating the generalprinciples of the invention; but it is to be understood that suchdetailed description is not to be taken in a limiting sense, since thescope of the invention is best dened by the appended claims.

Referring to the drawings:

Figure 1 is a longitudinal section, with parts shown in elevation, of adevice embodying the invention applied to drilling equipment disposed ina well bore;

Fig. 2 is a longitudinal section, on an enlarged scale, taken along theline 2*2 on Fig. l;

Fig. 3 is a cross-sectiony taken along the line 3 3 on Fig. 2.

The invention is disclosed in the drawings as applied to a device forstabilizing or centering a rotatable drilling string A in a well bore B.As is well known, the drill pipe A extends to the top of the hole, whereit is rotated by suitable equipment. The lower portion of the drillstring A may be constituted by a drill collar sub having an upper box 11threaded onto the lower pin end 12 of an adjoining drill pipe section13, the lower pin 14 of the sub being threaded into the box portion 15of a suitable rotary drill bit 16, for drilling the hole. During thedrilling operation, suitable circulating uid is pumped down the drillpipe A, which passes out through one or more nozzles or orifices 17 inthe drill bit, the circulating iluid carrying the cuttings up throughthe annulus 18 between the drill string A and the well bore B to the topof the hole.

For the purpose of appropriately stabilizing and centering the drill bit16 in the well bore, a suitable device may 2,758,891 Patented Aug. 14,1956 be mounted on the drill collar section 10. As shown in thedrawings, this centering device may consist of an elongate rubber orrubber-like sleeve 19 having an outside diameter slightly less than thediameter of the bore hole B being produced by the drill bit 16. Thissleeve 19 is not secured on the drill collar 10, but functions as abearing, the drill collar rotating therewithin. However, to permit thecuttings to be circulated out of the hole, the sleeve may be providedwith a plurality of circumferentially spaced and longitudinallyextending inclined grooves 2t) through which both the cuttings and thedrilling uid may pass in an upward direction.

As shown in the drawings, the centering or stabilizing device 19 isprevented from moving longitudinally along the drill collar member 10 byupper and lower retaining devices or structures 21 now to be described.Since the structures are identical, although oppositely arranged, adescription of the upper structure will su'lce for both. An annularretaining member 22, in the form of a ring, is disposed around the upperportion of the drill collar member 10, and extends outwardly from theperiphery of the latter to a certain extent. However, the diameter ofthe ring 22 is still substantially less than the diameter of the Wellbore B, to avoid interference with the upward passage of fluid throughthe annulus 18 between the drill pipe string A and the wall of the wellbore. The retaining member 22 is held in position on the drill collarmember 10 by a plurality of rollable retaining elements 23, in the formof balls, that are disposed within an external raceway 24 provided inthe periphery of the drill collar member 10, and also in an internalraceway 25 in the retaining ring 22. It is evident from the figures thateach ball 23 extends partially into both raceways or grooves 24, 25,which are of toroidal shape, and serves to lock the retaining ring 22 tothe drill collar or tubular member 10 against longitudinal movement withrespect thereto.

For reasons pointed out hereinafter, it is desired to prevent rotationof the retaining member 22 with respect to the drill collar 10. In thepresent instance, such rotation is precluded by one or morelongitudinally extending keys 26, which are inserted in opposed keyways27, 28 formed in the drill collar 10 and within the ring 22. Followinginsertion of the one or more keys 26 in the opposed keyways 27, 28, eachkey 26 is prevented from being removed by a transversely extending setscrew 29 threaded into the drill collar 10 at the base of the keyway 27and extending across the upper end of the key 26 itself. The key 26 isprevented from moving downwardly by engaging the bottom 30 of the keyway27.

In assembling the non-rotatable retaining device 21, the ring 22 isslipped over one end of the drill collar or sub 10, and is placed in aposition in which its raceway 25 is opposite the external raceway 24 ofthe drill collar member. The keys 26, which are disclosed as locateddiametrically opposite each other, can then be placed in the upper endsof the drill collar keyways 27 and slipped downwardly into the ring orsleeve keyways 28. Between the locking keys 26, the ring 22 is providedwith threaded holes 31 that are large enough to allow the balls 23 to beinserted therethrough and into the raceways 24, 25. When a plurality,such as two, keys 26 are used, then a pair of transversely extendingthreaded holes or bores 31 are employed, one group of balls 23 beinginserted through one hole until the raceway spaces between the keys 26are substantially completely filled, and another group of balls beinginserted through the other threaded hole 31 to substantially completelylill the raceway spaces between the keys on the other side of thedevice. Following insertion of the balls, plugs 32 are threaded into theholes to prevent the balls 23 from dropping out of place. Thetransveresly extending set screws 29 are then threaded into the drillcollar, to retain the keys 26 in place.

The centering or stabilizing device 19 may then be slipped over theother end of the drill collar member 10, its upward movement beinglimited by engagement of its upper end with the upper retaining ring 22,The, lower retaining device 2.1 is then assembled in place, its ring 22being engageable with the lower end of the Sleeve 19. The drill bit 16can then be threaded onto the pin end 14 of the drill collar member andthe latter then threaded onto the drill pipe, the entire assembly thenbeing lowered into the well bore B to its bottom. During the drillingoperation, the drill collar 10 will rotate inside the centering orstabilizing device 19, which functions as a bearing. Any tendency forthe centering device 19 to move substantially -in a longitudinaldirection with respect to the sub 10 is precluded by its engagement withthe upper and lower retaining rings 22, the longitudinal force beingtransmitted from each ring 22 through the balls 23 to the drill collar10 itself. in view of `the large number of balls 23 employed, and thefact that the balls, in eifect, function as an axial type of bear-ing,thrusts o-f large amounts can be transmitted between the stabilizingdevice 19 and the drill collar or pipe 10.

In the event the drill bit 16 becomes stuck in the hole, and it isnecessary to wash over and mill away the centering device 19, for thepurpose of freeing the bit and retrieving it from the hole, thenecessary wash-over or milling -tool can be lowered in the well bore B,and will pass over the box end 11 of the drill collar member 10, toengage `the upper retaining ring 22, which is preferably made of readilydrillable material, such as brass, so as to disintegrate under theaction of a cutting tool. Since the drill bit 16 and drill collar 10 arestuck in the hole, they are prevented from rotating. The keys 26effectively couple 'the retaining ring 22 to the drill collar, therebypreventing rotation of the ring. Accordingly, the washover tool can berotated, to operate upon the upper stationary retaining ring 22 anddisintegrate it. Following its disintegration, the wash-over tool cancontinue to disintegrate the centering device 19, then operating uponthe lower drillable ring 22, moving -on down beyond the latter, if needbe, for the purpose of freeing the equipment in the well bore andallowing it to be withdrawn to the top of the hole,

It is, accordingly, apparent that a retaining device 21 has beenprovided which is easily assembled and dismantled. 1n Athe eventdisassembly is required, it is merely necessary to unthread the plugs 32and withdraw the balls 23, which allows the ring 22 to be movedlongitudinally off the drill pipe member 10. In addition to thisadvantageous feature, the device is non-rotatable, thereby facilitatingits drilling away, and it also has a very great 'load transmittingcapacity, since longitudinally directed forces can be transmittedthrough the large surfaces provided by the raceways 24, 25 and throughthe balls 23.

The inventor claims:

l. In apparatus for stabilizing a tubular string in a well bore: aone-piece cylindrical tubular member; a stabilizing device on saidtubular member engageable with ,the wall of the well bore tosubstantially center the tubular member therein; means for preventingsubstantial longitudinal movement of said stabilizing device on saidtubular member in one direction, including an annular member on saidtubular member engageable with said stabilizing device, said tubularmember and annular member having opposed circumferential grooves,rollable elements in said grooves locking said annular member to saidtubular member against substantial longitudinal movement with respectthereto, opposed longitudinal` keyways in said tubular member andannular member, a key in said keyways, said annular member having a holearcuately displaced from said keyways through which said rollableelements are insertable in said grooves, and means closing said hole,said key in said tubular member extending lengthwise beyond the end ofsaid annular member to allow said key to be inserted in an endwisedirection into said opposed keyways, and means engaging said key toprevent its endwise removal from said keyways.

2. In apparatus for stabilizing a tubular string in a well bore: aone-piece cylindrical tubular member; a stabilizing device on saidtubular member engageable with the wall of the well bore tosubstantially center the tubular member therein; means for preventingsubstantial longitudinal movement of said stabilizing device on saidtubular member in one direction, including an annular member on saidtubular member engageable with said stabilizing device, said tubularmember and annular member having opposed circumferential grooves, ballsin said grooves locking said annular member to said tubular memberagainst substantial longitudinal movement with respect thereto, opposedlongitudinal keyways in said tubular member and annular member, a key insaid keyways, said annular member having a hole arcuately displaced fromsaid keyways through which said balls are insertable in said grooves,and means closing said hole, said keyway in said tubular memberextending lengthwise beyond the end of said annular member to allow saidkey to be inserted in an endwise direction into said opposed keyways,and means engaging said key to prevent its endwise removal from saidkeyways.

3. In apparatus for stabilizing a tubular string in a well bore: aone-piece cylindrical tubular member; a stabilizing device on saidtubular member engageable with the wall of the well bore tosubstantially center the tubular member therein; means for preventingsubstantial longitudinal movement of said stabilizing device on saidtubular member in both directions, including an annular member on saidtubular member engageable with the upper end of said stabilizing device,an annular member on said tubular member engageable with t-he lower endof said stabilizing device, said tubular member and each of said annularmembers having opposed circumferential grooves, balls in said grooveslocking said annular members to said tubular member against substantiallongitudinal movement with respect thereto, opposed longitudinal keywaysin said `tubular member and each of said annular members, a key in saidopposed keyways, each of said annular members having la hole arcuatelydisplaced from said keyways through which said 'balls are insertable insaid grooves, and means closing said holes, said key-ways in saidtubular member extending lengthwise beyond the ends of said annularmembers to allow said 'keys to be inserted in an endwise direction intosaid opposed keyways, and means engaging said keys to prevent :theirendwise removal from said keyways.

References Cited in the `file of Vthis patent UNITED STATES PATENTS

